This study is an epidemiologic investigation of identity, health risks, and stigma among gay, bisexual, and men who have sex with men (GB & MSM) in Moscow, Russia. The study goals are to explore the emerging identities among these men; optimize epidemiologic approaches to researching their health risks and health seeking behaviors; optimize recruitment methods for hard to reach subsets so as to bring them in for HIV/STI counseling and testing; and to understand the role that self, experienced and perceived stigma play in their lives. A social ecological framework will be used for the one descriptive and two methodologic aims. Aim 1 is descriptive and will explore the GB & MSM communities in Moscow. Formative qualitative research will investigate approaches to sampling and recruitment, and explore the physical and internet venues frequented by these men, and will inform the development of survey instruments, including a culturally- appropriate sexual identity measure, and online recruitment methods. Aim 2 is an assessment of optimal recruitment methods to access GB&MSM in Moscow and the relative efficiency of these recruitment methods to bring GB&MSM men in for HIV/STI counseling and testing. The recruitment efficiency and the ability of enhanced RDS and internet-based sampling (IBS) to access to GB&MSM subsets based on demographic characteristics, and sexual identity and orientation, history of HIV testing, and prevalence of undiagnosed HIV/STI will be assessed. We will also evaluate the efficiency of accrual into HIV testing and health care services among IBS recruited men. Aim 3 will investigate the epidemiology of self, perceived, and experienced stigma among gay identified and non-gay identified men in Moscow, measure the prevalence of stigma in these groups, and investigate the modifying role of stigma in the associations of sexual identity with behavioral risk, HIV/STI infection, and coping with human rights abrogations , stratifying by recruitment method. To accomplish these specific aims, formative research will include some 120 key informant interviews and focus groups with an additional 120 participants for survey instrument cognitive testing and scale validation. These will be followed by an enhanced RDS recruitment among 1140 GB & MSM in Moscow, and an IBS conducted concurrently among 1140 men recruited online. The stigma and human rights assessment will include a formative phase to adapt and refine the stigma scale, followed by integration of the scale into both the enhanced RDS and IBS recruitments. PUBLIC HEALTH RELEVANCE: Our goal is to conduct an epidemiologic investigation among MSM in Moscow, who are at substantial risk for HIV infection, to explore their sexual identities, health risks, and health seeking behaviors and to inform the development of interventions. We will endeavor to enhance Respondent-Driven Sampling and investigate the utility of Internet-Based Sampling as tools to recruit hard to reach subsets into HIV testing and health services.